A recent cosmic explosion has left astronomers baffled, with some proposing it could be a rare alignment of stars and others suggesting a previously unseen phenomenon. Designated EP240408a, the event was first detected by the Einstein Probe X-ray space telescope on April 8, 2024. Initially thought to be a gamma-ray burst, further observation revealed it didn’t fit into any known category.
A new study suggests that EP240408a may be the death throes of a white dwarf star being torn apart by a medium-sized black hole. This process created a high-speed jet of material pointing directly at Earth, which is unusual since jets from similar events typically don’t emit radio signals for hundreds or thousands of days.
The team’s findings indicate that EP240408a ticked some boxes but not all for various known phenomena. The short duration and high luminosity are difficult to explain in other scenarios. If future observations detect radio emissions, this could close the case on EP240408a; otherwise, it may be a unique gamma-ray burst or an entirely new type of transient event.
The discovery was made possible by a collaboration between multiple ground- and space-based telescopes, including NuSTAR, Swift, Gemini, Keck, and others. Astronomers continue to analyze the data, and while some signs point towards a tidal disruption event (TDE) as the most likely explanation, others remain uncertain.
Source: https://www.sciencealert.com/a-strange-new-cosmic-explosion-may-have-just-been-discovered